Shoe and method of manufacturing the same



April 26, 1938. F1 BRAND-r 2,114,993

SHOE AND METHOD OF MANUFACTURING THE SAME Filed Oct. 29, 1935 2Sheets-Sheet 1 April 26, 1938; F BRANDT 2,114,993

SHOE AND METHOD OF MANUFACTURING THE SAME Filed 001;. 29, 1935 2Sheets-Sheet 2 wvfwwar Patented Apr. 26, 1938- OFFICE SHOE; AND METHODOF MANUFACTURING THE SAME Francis L. Brandt, Wakefield, Mass., assignorto United Shoe cry Corporation, Paterson,

N. 3., a corporation of New Jersey Application October 29; 1935, SerialNo. 47,284

18 Claims. (01. 12-142) This invention relates to shoemaking and isillustrated as embodied in shoes the heels of which are attached withadhesives, and with reference to methods of attaching the heels to theshoes.

It is common practice to attach wood heels to shoes by nails or screwswhich are driven from the inside of the shoe after the last has beenpulled. While various finishing operations such as securing coveringflaps to the breasts of the heels, edge trimming, edge setting andscouring,

are being performed, the heel should form an integral part of the shoe,the shoe at this time preferably being on the last in order to maintain15 the shape of the shoe and to facilitate carrying out the aboveoperations. In order to avoid having to pull the last for the purpose'ofsecuring the heel to the shoe by inside nailing and then having toreinsert the last in the shoe, it is customary in the manufacture of thebetter grades of shoes to secure the heel temporarily by glue to theshoe preparatory to performing the various finishing operations. lifterthe shoe has been substantially completed and the last has been pulledthe heel is permanently secured to the shoe by nails or screws.

In order to retain as much as possible the pressure of the heel againstthe heel seat of the shoe for the purpose of preventing the shoematerials from springing back while the finishing operations are beingperformed and to insure that the heel seat shall set in permanentlymolded position, it is often the practice to use a temporary attachingscrew inserted as disclosed in United States Letters Patent No.1,502,014, grant; ed July 22, 1924 on an application filed in the nameof Frederic E. Bertrand.

In attaching the heel to the shoe temporarily by glue the heel isclamped with considerable pressure against the heel seat of the shoeupon the last for a period sufflcient to allow the glue to dry. Theheels may be temporarily attached to the shoes by the use of aheel-attaching machine of the turret type, for example as disclosed inLetters Patent of the United States No. 1.376.539, granted May 3, 1921on an application filed in the names of Isabelle Henne and John L. Free,in which heels are pressed upon the shoes for a substantial periodthereby permitting the glue to dry before the shoes are removed from themachine and go forward for subsequent. operations.

The results obtained when using the temporary attaching screw have beengenerally satisfactory. It has been found, however, that when glue aloneis relied upon to attach the heels temporarily to the shoes some oftherheels become detached before the heel-attaching nails or permanentscrews are inserted. Even though the heels do not become detached, theyfrequently spring away from their molded positions upon the heel seatsof the 5 shoes. Such a condition is unsatisfactory, particularly in thecase of Louis heel work in which the. heel has a covering flap securedto its breast and is seldom restored to its original position upon theshoe at the time of the permanent attaching 1o operation, with theresult that a wrinkle is formed in the flap in the vicinity of theheel-breast line of the shoe.

With the above and other considerations in view and in accordance with afeature of the pres- 15 ent invention, I propose toprovide a shoe and aheel which is to be attached to the shoe with anchoring means, and tointerpose a mass of hot thermoplastic material between the heel and theshoe. The heel is then pressed against the heel seat of the shoe toforce the thermoplastic material into interlocking engagement with saidanchorlng means, pressure of the heel against the shoe being maintaineduntil the thermoplastic material cools and hardens.

When a quantity of thermoplastic adhesive is used to attach the heel tothe shoe, the time dwell during which the heel need be held against theheel seat with molding pressure is reduced materially and there islittle danger of the heel becoming loose as the operator performs thevarious finishing operations. When the last has been removed from theshoe the thermoplastic material may, if desired, be supplemented bynails or screws. Furthermore, by utilizing an undercut or reentrantcavity in the attaching face of the heel and a similar cavity or otherappropriate anchoring means in the heel-seat portion of the shoe, thethermoplastic material may be forced to take 40 the form of a' rivetwhich, after it has set, has such a strength and permanence and such aninterlocking engagement with the shoe and heel as will enable it toserve as the entire heelattaching means. The thermoplastic material, 45

- preferably in the form of a plug, is insertedin one of the undercutcavities and the heel is. forced with molding pressure against the heelseat while the plug is in moldable condition; the heel being thenclamped against the heel seat 50 until the heel seat has becomepermanently molded and until. the thermoplastic material has set. Theplug should be of a size to fill both the cavities as well as to fill,so far as practicable, the

space included between the attaching face of the 55 heel and the heelseat of the shoe, as well as all the insole 34, (Fig. 3) of the shoe.During the interstices or voids in the latter. With the abovearrangement the heel is effectively secured to the shoe upper by alarge'rivet of hardened material which may be said to be clenched to theheel and to the heel seat and its respective ends and which is ofsuflicient strength to'serve as the entire heel-attaching means.

In order to provide an exceptionally strong and durable form-retainingheel end structure for the shoe a further feature of the inventionresides in the provision of an insole having a. fibre reenforcementattached thereto extending to the margin of the heel seat, whichreenforcement has a projecting portion which may be embedded in thehardened mass of thermoplastic cement in a. manner to hold theoverlasted margin of the shoe upper tightly clamped between thereenforcement and the rim of the heel. It is further contemplated that ashank stiffener be locked in the mass of thermoplastic material and thismay be done either independently of the above-mentioned reenforcement orby combining the shank stiffener and the reenforcement as a single unitthereby obtaining in a maximum degree the qualities of strength andrigidity which are so desirable in the heel portion of a shoe.

The above and other features of the invention in both its method andshoe structure aspects will be better understood and appreciated fromreading the following detailed description there- I of in connectionwith the accompanying drawings, in which Fig. 1 is a perspective view ofa shoe upon a last, the heel-seat portion of the sole of the shoe havingbeen fitted for the reception of a Louis heel;

Fig. 2 shows in perspective a heel with a mass of thermoplastic adhesiveapplied to its attaching face, and a tool for applying the adhesive tothe heel;

Fig. 3 is a perspective view, partly in section, showing the heel ofFig. 2 after it has been forced with moldingpressure against the heelseat of the shoe ofFlg. 1; I

Fig. 4 is a perspective view of a sole having a fibre reenforcementsecured thereto;

Fig. 5 shows a covered Cuban heel having an undercut cavity in itsattaching face;

Fig. 6 is a perspective view, partly in section,

of the heel end of a shoe having a short outsole,

Fig. 9 is a transverse section taken through the heel end of the shoeafter the heel has been permanently attached to the shoe.

In the manufacture of the shoe 22, which is illustrated asmounted onelast 24, a pair 01' I heel-breast receiving shoulders. l8 (Fig. 1) havebeen formed upon the sale 20 and the heel-seat portion of the sole hasbeen reduced thereby providing a tongue 26 of suitable shape'to beincluded within the attaching face 28v of a wood heel 30, tacks 32 beingemployed, in accordance with usual practice, to secure the tongue 26 toheel-attaching operation the rim 36 of the attaching face 28 of the heel30 is forced with molding pressure against the overlasted counterportion 38 of the shoeupper, the rim forming a shallow groove 40 (Fig.3) in the previously somewhat rounded margin 42 (Fig. 1) of the heelseat of the shoe.

In order to insure that the heel 30 may be effectively secured to theshoe 22 while various finishing operations are being performed upon theshoe and until the last 24 has been pulled and the heel has been nailedor otherwise permanently attached to the shoe, I propose to interpose asubstantial quantity of thermoplastic adhesive 44 between the heel 30and the heel seat of the shoe 22, the heel then being forced withmoldingpressure against the heel seat of the shoe and being clamped inmolding relation with the heel seat for a period of sufficient durationto insure thesetting of the adhesive.

The thermoplastic adhesive 44 may conveniently be applied to theattaching face 28 of the heel 30 by a plate 46 of suitable shape.Although the thermoplastic adhesive 44 is illustrated with- The heel 30may be effectively forced against the heel seat of the shoe 22 mountedupon a support 48, by a tread clamp 50 and a back clamp 52 constructedand arranged to engage a thick leather apron 54 which covers the rearface of the heel, the shoe being positioned lengthwise relatively to theclamps by a back gage 56. A machine which comprises the above-mentionedelements and which may be advantageously used for clamping heels toshoes, is disclosed in United States Letters Patent No. 2,076,537,granted April 13, 1937 on an application filed in the name of Bazzoni, acovering flap 51, in accordance with a preferred practice, being appliedto the breast of the heel by the machine while the heel is held undermolding pressure against the shoe. When heels are temporarily attachedto shoes by thermoplastic adhesive as above described there is little,if any, trouble experienced due to the heels becoming loose betweentemporary and permanent heel-attaching operations.

While it may be impracticable to attempt to fill absolutely all thevoids or interstices included between the attaching face of the heel andthe heel seat of the shoe, since it is desirable to insure that thethermoplastic adhesive 44 shall not .seep from between the rim 36 of theheel 30 and the counter portion of the shoe, nevertheless by usingreasonable care and an appropriate quantity of thermoplastic materialthese spaces may be substantially filled. It will be understood that theheel-seat portions of the soles may be reduced to various shapes, theamount of thermoplastic adhesive used varying .in accordance with theshape of the reduced heel seat.

In order permanently to secure heels to shoes by thermoplastic adhesivewithout the aid of nails or screws, the procedure illustrated in Figs.

4 to 9 may be utilized. In those figures a shoe 58 is provided with aCuban heel 80 which is secured to the shoe by a rivet 62 of hardenedthermoplastic adhesive, best shown in Fig. 9. The insole 64 (Fig. 4) ofthe shoe 58 has a fibre'reenforcement 66 adheslvely or otherwise securedto it, the reenforcement having a channel 68 for receiving a shankstifl'ener I and a hollow frustoconical projecting portion I2 which islocated at the rear end of the channel and maybe described as beingfunnel-shaped with its smaller end'projecting from the insole. Theattaching face 14 (Fig. 5) of the heel 60 is provided with an undercutconical cavity 16. After the shoe 58 has been lasted the shank stiffener10 is tacked or otherwise secured to the insole, the stifiener being ofsuitable shape to fit within the channel 68 of the fibre reeniorcement68 and having a' bent rear end 18 which extends into the hollow conicalprojecting portion I2 of the fibre reenforcement 66. A short outsole 80provided with a heel-breast receiving shoulder 82 (Figs. 6 and 7) isthen attached to the shoe 58. The rivet 62 of thermoplastic adhesive isformed from a, lump or plug 84 which, after being heated to the propermoldable temperature, is inserted within the cavity 16 (Fig. '7) of theheel 60. The shoe 58 is then mounted upon the support, 48 and the heel60 is forced, for example by the use of the heel-attaching machine abovereferred to, against the heel seat of the shoe which may be described ashaving a reentrant or undercut cavity 86 (Fig. 6). The lump or plug 84of thermoplastic adhesive may be inserted in the cavity 86 (Fig. 8) ofthe heel instead of being inserted in the cavity 16 of the heel. Thehardened rivet 62 of thermoplastic adhesive fills the undercut orreentrant cavities I6, 86 and also fills a considerable portion,preferably all or substantially all, of the space between the heel seatof the shoe and the attaching face of the heel.

The heel is clamped in molded relation with the shoe for a periodsuflicient to insure the hardening of the thermoplastic material, theheel thereafter being held securely in its molded position upon the shoeby the rivet 62 of hardened thermoplastic adhesive which may be said tobe clenched at opposite ends within the undercut cavities I6, 86. In theillustrated construction the bent rear end I8 of the shank stiffener I0is preferably embodied within the rivet 62 and in combination with thefibre reenforcement 66 secures the heel to the rear end of the shoeupper and provides an exceptionally strong and durable form-retainingheel end structure for the shoe. N

A thermoplastic adhesive which may be eflectively used for attachingheels to shoes is disclosed in United States Letters Patent No.1,945,803, granted February 6, 1934 on an application filed in the nameof Myron E. Delaney.

Ha'ving described the invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

1. The method of attaching heels to shoes which comprises providing a.shoe upper which has a reentrant cavity in its heel seat, providing aheel having a reentrant cavity in its attaching face, interposing aquantity of moldable thermo-- plastic adhesive between said heel seatand said attaching face, clamping the heel under heavy molding pressureagainst the heel seat while the adhesive is in a moldable conditionthereby causing the same to fill said cavities as well as to fill voidsincluded betweenthe attaching face of the heel and the heel seat, andmaintaining the heel clamped to the heel seat for a period sufficient toinsure the setting of the adhesive.

2. The method of attaching a heel to a shoe 1 which comprises providingrecesses in the heel and the shoe, interposing a mass of self-hardeningplastic material in a plastic condition between the heel and the shoe,pressing the heel against the heel seat of the shoe to force the plasticmaterial into said recesses, and permitting the plastic material toharden.

3 The method of attaching a heel to a shoe which comprises providingcavities in the heel and the shoe, interposing a mass of hotthermoplastic material between the heel and the shoe, pressing the heelupon the shoe to force the thermoplastic material into said cavities,and permitting said material to cool and harden.

4. The method of attaching a heel to a shoe which comprises providingthe heel and the shoe with anchoring means, interposing a mass of hotthermoplastic material between the heel and the shoe, pressing the heelupon the. shoe to force the thermoplastic material into interlockingengageing element having a projecting portion, lasting an upper andcounter over the'insole and securing them thereto, attaching an outsoleto the shoe leaving the projecting portion of said reen forcing elementexposed, providing a heel with an anchoring means, interposing a mass ofplastic material between the heel and the heel seat of the shoe,pressing the heel against said heel seat to force the plastic materialinto interlocking engagement with said anchoring means and theprojecting portion of said reenforcing element, and permitting saidplastic material to harden.

6. The method of securing a heel having an undercut cavity in itsattaching face to a shoe provided with a heel seat having an undercutcavity, comprising inserting a plug of moldable thermoplastic adhesiveinto one of said cavities, forcing the heel against the heel seat withmolding pressure while the plug is moldable to cause said adhesive tofill said cavities and to fill at least a substantial portion of thevoids included between said heel seat and said attaching face, andmaintaining pressure of the heel against the heel seat until theadhesive has set thereby permanently securing the heel to the shoe.

7.- A shoe the heel and heel seat of which have undercut cavities filledwith a hardened mass of plastic material which is ofsufiicient strengthto secure the heel permanently to the shoe.

8. A shoe the heel-seat portion of which has an undercut cavity, a heelengaging said heelseat portion and also having an undercut cavity,

said heel being secured to the shoe by a rivet consisting oi a hardenedmass of thermoplastic material engaged in and substantially filling bothof said cavities.

9. A shoe having a heel seat provided with a cavity, a shank stiflener,and a heel engaging said heel seat andhaving a cavity in its attachingface, the heel being secured to the heel seat by a hardened mass ofplastic material interengaging the cavities in the heel and the heelseat and permanently embedding and locking a portion of the stiflener.

10. A shoe having a heel seat containing a reentrant cavity, a heelhaving a reentrant cavity in its attaching face, a mass of hardenedplastic the heel to the shoe, and a shank stiil'ener the rear end ofwhich extends into the cavity in the heel seat and is embedded andlockedin said material.

11. A shoe the heel end of which comprises an insole, a rigidreenforcing member attached to the lower face of the heel portion of theinsole, said member extending substantially to the margin of the heelseat of the shoe and having a hole in its central portion to provide acavity the bottom' of which is formed by the insole, a heel having anattaching face provided with a cavity, a shoe upper having an overlastedmargin clamped between the reenforcing member and the heel, anda massofhardened plastic material interlocked within said cavities and servingto maintain the edge of the heel tightly against the heel seat.

12. A shoe having a heel provided with a cavity in its attaching face,an insole, a reenforcing member which is secured to the lower face ofthe insole and has an anchoring portion extending toward the heel, and ashank stiffener the rear end of which extends toward the heel, all ofthe above parts being secured together by a mass of hard thermoplasticmaterial.

13. A shoe having an insole, a fibre reenforcement secured to the lowerface of the insole, said reenforcement having a hollow, frusto-conicalportion the smaller end of which projects from the insole and a heelhaving an-undercut cavity in its attaching face, all of the parts beingsecured together by a hardened mass of plastic material substantiallyfilling the hollow frustoconical portion of the reenforcement and theundercut cavity of the heel.

14. A shoe having an insole, a heel the attacha ing face of which isprovided with an undercut recess, a fibre reenforcement secured to thelower face of the insole, said reenforcem'ent having a funnel-shapedportion the smaller end of which projects toward the heel, and a shortoutsole, all of said parts being engaged and securedtogether by ahardened mass of plastic material.

15. A shoe having a heel provided with an undercut cavity in itsattaching face, an insole, V a reenforcing member secured to the lowerface of-the insole and having a funnel-shaped projection the smaller endof which extends toward the heel, a shank stiflener the rear end ofwhich extends toward theheel and into the funnelshaped projection, allof theabove parts being engaged and secured together by a hard mass ofthermoplastic material.

16. A step product consisting of a shoe ready to receive a heel, saidshoe being provided with a cavity which is included within the heel-seatof the shoe and is limited in depth by the insole of the shoe, and amass of thermoplastic material in said cavity.

17. A step product consisting of a shoe ready to receive a heel, saidshoe being provided with an undercut cavity which is included within theheel seat of the shoe andis limited in depth by the insole of the shoe,and a mass of thermoplastic material in said cavity.

18. An insole for use in the manufacture of shoes having a relativelyrigid reenforcement se-,

